Daylight film developing tank

ABSTRACT

A daylight developing tank of roll films for simultaneously developing a plurality of comparatively short roll films. The tank includes a spool having a plurality of film-holding grooves, each of which grooves holds a film only at the upper and lower edges thereof. Film retainers are secured to the film-holding grooves, respectively, for retaining the outermost end of each film being loaded in a cassette, which cassette is disposed adjacent the spool during the development.

United States Patent Katsuragi [.51 3,703,859 Nov. 28, 1972 22 Filed:

v 21 Appl.N0.: 27,849

[54] 'DAYLIGHT DEVELOPING TANK [72] inventor: Mamoru Katsuragi, lzumi,Japan 73 Assignee: Minolta Camera Kabushiki Kaisha,

Osaka, Japan April 13, 1970 52 us. Q ..95/905, 95/93, 95/9412 Brorns..95/90.5

1,274,651 '8/191 8 Windrim et a1 ..95/90.s

- 7 2,298,963 10/1942 Naylor et al. ..9s/90.5

3,140,647 7/1964 Miller ..95/93 FORHGN PATENTS OR APPLICATIONS 560,0053/1944 Great Britain ..95/9o.5

Primary Examiner-Sa1nuel s. Matthews Assistant Examiner--Alan A. MathewsAttorney-Starfley Wolder ABSTRACT A daylight developing tank of rollfilms for simultaneously developing a plurality of comparatively shortroll films. The tank includes a spool having a plurality of film-holdinggrooves, each of which grooves holds a film only at the upper and loweredges thereof. Film retainers are secured to the film-holding grooves,respectively, for retaining the outermost end of each film being loadedin a cassette, which cassette is disposed adjacent the spool during thedevelopment.

5ClainB,3DrawingFigures PATENTED um: 28 I912 SHEET 1 [1F 2 i li iiINVENTOR.

Y man onu knTauxnai PATENTEDnuv 2a 1912 sum 2 or 2 FIG.2

1 DAYLIGI-IT FILM DEVELOPING TANK This invention relates to a daylightfilm developing tank, and more particularly to a developing tank forsimultaneously developing a plurality of comparatively short roll filmsunder daylight.

A typical roll film of comparatively short type, which is commonly usedat the present moment, is a 16-mm roll film. For instance, according to.118 (Japanese lndustrial Standard) B 7176 Shape and Size of 16-mmCamera Patrone (Cassette) (DRAFT), the standard film length is 475 mm.The recent trend with such films is to provide as a large picture areaas possible without increasing the film width, so as to improve thepicture quality. Accordingly, the spacing from the edges ofthe picturearea to the edges of the film is getting smaller. For instance,according to JlS B 7176 Shape and Size of l 6-mm Camera Patrone (DRAFT),the spacing from the lower edge of the picture area to the lower edge ofthe film is only 1 mm, in the case of 12 X 17 mm picture area.

Due to such trend in 16-mm films, it is becoming increasingly difficultwithconventional developing tanks of belt type or groove type multipleroll system to properly treat the film without scratching the picturearea thereof during the loading in the tank, or without causing'anyuneven development created by contacts of adjacent film portions. As aresult, considerable skill and prudence are required for the loading andtreating of the film in the developing tank. In the case of a developingtank of spiral single-layered roll type, the body of the developing tankincludes a patrone loading means (e.g., a peripheral projection) forreceiving a cassette, and during agitation of the developer in the tank,the flow of the developer is apt to be disturbed by the cassette loadingmeans. As a result, turbulence may be caused, which possibly leads touneven development of the film.

Furthermore, with known daylight developing tanks, only one roll filmcan be developed at a time. Since 16- mm roll films include only afewframes per roll, there has been a demand for a daylight developing tankcapable. of simultaneously developing a plurality of roll films.

Therefore, an object of the present invention is to obviate theaforesaid difficulties of the known daylight developing tank, byproviding an improved daylight developing tank, which is capable ofdeveloping a plurality of roll films at a time, depending on the need.

With the developing tank of the present invention, the film beingdeveloped is held in such a manner that, although turbulence of thedeveloper may be caused by a patrone holding means (e.g., the radialextension of a tank body) in response to developer agitation, suchturbulence will not result in any uneven development. The film may beloaded in the tank of the present invention without touching theemulsion of the film, so that the film may be held in the tank byretaining only the upper and lower edges thereof. Thus, the pictureareas of the film will never be scratched or soiled during thedevelopment in the tank of the invention.

Other objects and advantages of the present invention may be appreciatedby referring to the following descriptiomtaken in conjunction with theaccompanying drawings, in which:

tank. Like parts are designated by like numerals- FIG. 1 is a verticalsectional view of a daylight developing tank, according to the presentinvention, shown in the state as completely assembled with a spool and acover mounted on a tank body;

FIG. 2 is an exploded perspective view of the developing tank with afilm patrone mounted thereon; and

FIG. 3 is a perspective view of a patrone for a 16-min film, which ismountable on the daylight'developing throughout the drawings. I

Referring to FIG. 1, a preferred embodiment of the present inventionincludes a cup-shape spool 4 having a circumferential lengthsubstantially equivalent to the length of each roll film to be developedtherein. A knob 3 with a central aperture 2 is integrally formed at theupper end of the spool 4. Two film-holding grooves 5 are formed on theperipheral surface of the spool, with a suitable axial spacing betweenthem. Each of the fi1m-. holding groove 5 holds a roll film 1 byoperatively engaging only upper and lower edges thereof. A film retainer6 is provided on each film-holding groove 5 for resiliently retainingthe longitudinal end portion of each roll film, as shown in FIG. 2. Tofacilitate flow of a liquid developer through the cup-shape spool 4, aplurality of downwardly extending projections 7 are provided on theannular bottom wall of the spool at uniform angular intervals about thevertical axis of the spool, so as to form passages of the liquiddeveloper between the annular bottom wall of the spool and the uppersurface of the bottom wall of a tank body 18, to

be described hereinafter. The shape and the position of such projections7 are so selected that the disturbance of the flow of the liquiddeveloper due to the presence of such projections is minimized.

. A cover 9 is engageable with the top of the cup-shape spool 4, whilerotatably fitting the knob 3 of the spool 4 is a central aperture 8 ofthe cover 9 in axial alignment therewith. As best shown in FIG. 2, aradial projection 10 is integrallyformed with the cover 9, so that twocylinders 15, each having a resilient cassette cassette holder 14, canbe mountedon the lower surface of the projection 10. The cylinder 15 andthe cassette holder 14 extend substantially at right angles to the planeof the projection 10. The patrone holder 14 resiliently engages thecentral driving hole 13 of each patrone 12.

In FIG. 3, in order to develop each exposed film I mounted on thecassette 12, a bridging portion 11 of the patrone 12 is split, and thecassette 12 with the film thus separated is mounted on the cylinder 15of the cover 10, by inserting the resilient cassette holder 14 into thedriving hole 130! the cassette 12. Thus, the

outer end of the roll film 1 in the cassette 12 can be placed adjacentthe film-holding groove 5 of the spool 4. A vertical light-interruptingwall 16 is formed along the periphery of the cover 9. g

A body 18 includes a cylindrical portion for rotatably receiving thecup-shape spool 4 and a radial extension 17, integrally formed with thecylindrical portion, for receiving the cylinders 15 with the cassetteholders 14. The cover 9 with the radial projection 10 fits on the topopenings of the cylindrical portion and the radial extension of the body18. Another vertical light-interrupting wall 19 is integrally formedwith the peripheral wall of .the patronei The cover 9 is mounted on thespool 4,

and at the same time, the outer end portion of the exposed film l isinserted between the outer peripheral surface of the film-holding grooveand the resilient lug portion of the film retainer 6, for resilientlyholding the end portion of the film l in the film-holding groove.

The spool 4 and the cover 9 thus assembled is mounted on the tank body18, as shown in FIGS. 1 and 2. A dark chamber is formed by the body 18,the cover 9, and the light-interrupting walls 16, 19, so that theexposed film l is rotatably held in such dark chamber. As the knob 3 isrotated counter-clockwise, as seen in FIG. 2, the exposed film l iswithdrawn out of the cassette 12 along the film-holding groove 5 of thespool 4, while holding only the upper and lower edges of the film 1.Since the inner end portion of the film 1 is secured to the core of thecassette 12, the operator can sense by feeling when the entire length ofthe film 1 is withdrawn from the cassette 12, because the resistance tothe counterclockwise rotation of the spool 4 will suddenly increase atthis particular moment. After mounting the full length of the exposedfilm l on the film-holding groove 5 of the spool 4, liquid developer ispoured into the body 18 of the developing tank through the centralaperture 2- of the knob 3 of the spool 4, while keeping the cover 9fitted on the top portion of the body 18.

i Then, the film 1 is developed by agitating the liquid developer byshaking the entire developing tank. After a predetermined developingtime, the liquid developer is poured out of the developing tank, whilekeeping the spool 4 and the cover 9 as mounted on the body 18.

Although the present invention has been described with a certain degreeof particularity, it is understood that the present disclosure has beenmade only by way of example and that numerous changes in the details ofconstruction and arrangement of parts may be resorted to withoutdeparting from the spirit and the scope of the invention, as hereinafterclaimed.

What is claimed is:

1 A daylight developing tank of roll films, comprising a tank bodyincluding a cylindrical portion and a radial extension; a cylindricalspool rotatably engageable with the cylindrical portion of the body andhaving a plurality of separate, vertically spaced, horizontal, annularfilm-holding grooves circumferentially formed on the peripheral outersurface of the spool, the circumference of the spool being at least thesame in length as films being developed, the film-holding grooveengaging only upper and lower edges of a single length of film: aooverincluding a circular portion and a radial projection engageablewith the cylindrical portion and the radial extension of the tankrespectively, in a lightinterrupting manner at the top thereof, saidcover having an aperture rotatably engageable with the spool; aplurality of cassette holders securedto the lower surface of the radialprojection of the cover so that when thecover and spool are so engagedthe holders extend various distances-along the on er surface of thespool so as to dispose cassettes adjacent to respective filmholdinggrooves, and a plurality of film retainers, each being mounted on thefilm-holding groove for retaining the outermost end of the film from thecorresponding cassette carried by the cassette holder.

2. A daylight developing tank according to claim 1, wherein said spoolhas a knobintegrally formed therewith and extending through the apertureof the cover in a rotatable manner.

3. A daylight developing tank according to claim 1, wherein said filmretainers are made of resilient lug members, so as to urge the outermostend of each film being developed against the outer surface of thefilmholding groove.

4. A daylight developing tank according to claim 1, wherein said coverhas a vertical light-interrupting wall integrally formed along theperiphery thereof, and the body has another light-interrupting wallintegrally formed with the peripheral wall thereof at the uppermost edgethereof so as to cooperate with light-interrupting wall of the cover,for defining a dark chamber receiving the film being developed.

5. A daylight developing apparatus for roll films, comprising a tank forcontaining developer including a cylindrical portion and a radialextension; a cylindrical spool coaxially and rotatably engageable withthe cylindrical portion of the tank in the interior thereof and having aplurality of independent film-holding grooves circumferentially formedon the periphery of the spool, each of said-independent grooves beingarranged substantially in parallel with each other with an axial spacetherebetween and having a circumference substantially the same as thelength of the film to be developed, each of said grooves having suchconfiguration in its axial section as to engage only the side edges ofthe film; a cover including a circular portion and a radial projectionengageable respectively with the cylindrical portion and the radialextension of the tank in a light-interrupting manner at the top thereof,said cover having an aperture rotatably engageable with the spool; aplurality of film cassette holders secured to the lower surface of theradial projection of the cover so as to dispose each of the filmcassettes adjacent the corresponding film-holding groove when the coveris mounted on the tank; and a plurality of film retainers, each beingmounted in a film-holding groove for retaining the leading edge of thefilm in the corresponding film cassette carried by the film cassetteholder.

1. A daylight developing tank of roll films, comprising a tank bodyincluding a cylindrical portion and a radial extension; a cylindricalspool rotatably engageable with the cylindrical portion of the body andhaving a plurality of separate, vertically spaced, horizontal, annularfilm-holding grooves circumferentially formed on the peripheral outersurface of the spool, the circumference of the spool being at least thesame in length as films being developed, the film-holding grooveengaging only upper and lower edges of a single length of film: a coverincluding a circular portion and a radial projection engageable with thecylindrical portion and the radial extension of the tank respectively,in a light-interrupting manner at the top thereof, said cover having anaperture rotatably engageable with the spool; a plurality of cassetteholders secured to the lower surface of the radial projection of thecover so that when the cover and spool are so engaged the holders extendvarious distances along the outer surface of the spool so as to disposecassettes adjacent to respective film-holding grooves, and a pluralityof film retainers, each being mounted on the filmholding groove forretaining the outermost end of the film from the corresponding cassettecarried by the cassette holder.
 2. A daylight developing tank accordingto claim 1, wherein said spool has a knob integrally formed therewithand extending through the aperture of the cover in a rotatable manner.3. A daylight developing tank according to claim 1, wherein said filmretAiners are made of resilient lug members, so as to urge the outermostend of each film being developed against the outer surface of thefilm-holding groove.
 4. A daylight developing tank according to claim 1,wherein said cover has a vertical light-interrupting wall integrallyformed along the periphery thereof, and the body has anotherlight-interrupting wall integrally formed with the peripheral wallthereof at the uppermost edge thereof so as to cooperate withlight-interrupting wall of the cover, for defining a dark chamberreceiving the film being developed.
 5. A daylight developing apparatusfor roll films, comprising a tank for containing developer including acylindrical portion and a radial extension; a cylindrical spoolcoaxially and rotatably engageable with the cylindrical portion of thetank in the interior thereof and having a plurality of independentfilm-holding grooves circumferentially formed on the periphery of thespool, each of said independent grooves being arranged substantially inparallel with each other with an axial space therebetween and having acircumference substantially the same as the length of the film to bedeveloped, each of said grooves having such configuration in its axialsection as to engage only the side edges of the film; a cover includinga circular portion and a radial projection engageable respectively withthe cylindrical portion and the radial extension of the tank in alight-interrupting manner at the top thereof, said cover having anaperture rotatably engageable with the spool; a plurality of filmcassette holders secured to the lower surface of the radial projectionof the cover so as to dispose each of the film cassettes adjacent thecorresponding film-holding groove when the cover is mounted on the tank;and a plurality of film retainers, each being mounted in a film-holdinggroove for retaining the leading edge of the film in the correspondingfilm cassette carried by the film cassette holder.